Earthmoving and construction type machines, which have endless self-laying track chain assemblies for support and propulsion, generally utilize a sprocket wheel to engage and drive the track chain. Several different types of sprocket wheels have been used in the past. These include a single wheel member having a plurality of integral teeth, hub members which accommodate a plurality of separate individual teeth, and a circular support member for supporting multiple segments, with each segment having several teeth. Each segment is generally connected to the circular support member by a plurality of threaded fasteners and cooperating threaded nuts.
One type of drive sprocket having a plurality of separate individual teeth connected to a hub portion is disclosed in U.S. Pat. No. 2,365,544, issued to H. D. Geyer et al. on Dec. 19, 1944. In this patent, the teeth are fulcrumed to the hub portion somewhere near the middle of the teeth so the teeth can rotate in either direction about the fulcrum. Resilient means are provided to return the teeth to their original no load position. This arrangement is intended to make the teeth self-adjusting to accommodate variations in the track chain.
Another type of sprocket wheel, having a plurality of segments with several teeth on each segment, is shown in U.S. Pat. No. 4,511,186, issued to T. Sasamoto on Apr. 16, 1985. In this patent, the teeth segments are connected to an outer tube by a plurality of threaded bolts and nuts.
Each of the above-noted sprocket assemblies provides replaceable drive teeth, either individually or in segments. However, the teeth are secured to a support member so that they are intended to deflect, or by bolts and nuts which may allow deflection of the segments under heavy loads.
The present invention is directed to overcoming one or more of the problems, as set forth above.